A flex wing apparatus is any apparatus which derives its support or motive power, in whole or in part, from a flexible wing. Examples of flex wing apparatus include sail boats, windsurfers, hang gliders and land sailing apparatus. The flex wing itself can for example, be a sail for a boat together with the associated mast.
The performance of a flex wing apparatus is dependent upon the efficiency of its flex wing. In order to adapt a flex wing for particular wind conditions, the camber of the wing can be adjusted.
In a typical flex wing, resilient battens are carried by batten pockets in the sail, and the shape or camber of the sail is determined by the dimensions and shape of the sail itself, the shape of the mast and the spacing allowed between the mast and the trailing end of battens in the sail. Provision can be made for adjusting these parameters, for example by altering the tension in the leech of the sail, the downhaul tension at the sail luff, or the outhaul tension on the sail. When the camber or curvature of the sail is increased, a forward force is applied to the battens which, unless otherwise resisted, will force the battens against or around the mast.
In my prior applications referred to above, flex wing apparatus are disclosed in which the movement of the leading end of battens in a sail are controlled by couplings between the battens and the mast which ensure that battens cannot advance into direct engagement with or around the mast in a manner which will distort the sail adjacent the mast and thereby adversely affect the performance of the sail.
In many contemporary flex wing apparatus, a sail is formed with a sleeve at its leading or luff edge, and the sail is mounted on the mast by the mast being received in this luff sleeve. As described in my earlier applications referred to above, the couplings thereof can be disposed within such a luff sleeve, with the battens in the sail extending forwardly thereinto. The couplings are connected to the battens proximate the trailing edge of the luff sleeve; i.e., near the line or seam that defines the forward boundary of the single sheet of flex wing material that forms the main body of the sail.